<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>按从大到小排序</title>
</head>
<body>
    <script>
        //定义数组arr
        var arr=[70, 67, 49, 35, 59, 98, 100, 20];
        //冒泡排序
        for(var i=0 ;i<arr.length-1; i++){
            for(var j = 0;j<arr.length-1-i; j++){
                if(arr[j] < arr[j+1]){
                    var temp = arr[j];
                    arr[j] = arr[j+1];
                    arr[j+1] = temp;
                }
            }
        }
    //弹出窗口显示排序后的数组
    alert(arr);
    </script>
</body>
</html>